Dennis Ross was the chief Middle East peace negotiator for the United States during the Clinton administration. He is the author of "The Missing Peace: The Inside Story of the Fight for Middle East Peace" (Farrar, Straus and Giroux, 2004) and acounselor at the Washington Institute for Near East Policy.

By Dennis Ross

WASHINGTON — Since the 1994 signing of the Gaza-Jericho agreement in Cairo — when Yasser Arafat disrupted the ceremony and embarrassed Egyptian President Hosni Mubarak — Egypt has done little to promote progress between Israelis and Palestinians. True, President Mubarak might host events or even send his intelligence chief, Omar Suleiman, to try to broker understandings among Palestinian factions. But the extent of the Egyptian commitment was limited, and Mubarak was never again ready to put his standing and reputation on the line.

Now, however, with Arafat gone, Egypt is turning a new and welcome page. It has reached an understanding on "qualified industrial zones" with Israel, agreed to an increased presence on the Sinai-Gaza border to prevent smuggling of arms into Gaza, released from jail Azzam Azzam (an Israeli Druze whom President Mubarak had long refused to release), and made declarations about Israeli Prime Minister Ariel Sharon being the man who can deliver on peace.

If that were not enough, President Mubarak has uncharacteristically intervened in Palestinian politics, calling for support of Abu Mazen's candidacy to head the Palestinian Authority and publicly urging Marwan Barghouti not to run. What is going on? Put simply, President Mubarak understands that Arafat's passing provides a brief opening to create a responsible Palestinian leadership — and that opening cannot be missed.

So, Egypt will do its part to work with the Palestinians, helping both to broker understandings on an internal cease-fire and to support the overhaul of the Palestinian security organizations and training of new security forces. As important as Egyptian efforts are, however, Egypt knows it is no substitute for the United States. Only America can build bridges between the Israelis and Palestinians, mobilize the Europeans, and effectuate necessary Arab assistance.

Given the stakes and the transient character of the current opening, it is important for the United States to act on several parallel tracks. First, the United States must help orchestrate a resumption of a dialogue between Israelis and Palestinians to forge understandings on what each will do to stop their ongoing war.

While it might have been useful to have done this even prior to the Palestinian elections, it will be essential afterward, when Abu Mazen must show that he can transform the reality on the ground. Palestinians want the Israelis to lift checkpoints, stop targeted killings, halt incursions into their cities and towns, and cease making arrests. The Israelis will do so only if Palestinians prevent attacks against Israelis — whether within or outside the "green line."

Here is the making of a bargain, but it must be directly negotiated. The cease-fire in the summer of 2003 failed because there were no direct understandings between the Israelis and Palestinians; they must have a common understanding of what each is going to do and not do. Without that, there inevitably will be failed expectations on each side and a sense of betrayal when problems emerge. None of this will happen on its own, except, of course, the problems.

Second, the United States needs to work with the Europeans to emphasize publicly that calm is a condition for holding the elections both for the president of the Palestinian Authority this month and the Legislative Council in May. There is a strong Palestinian consensus in favor of these elections; Palestinians know that to prevent the competition for power after Arafat from turning violent, they need elections.

To raise the costs to Hamas, Islamic Jihad and the al-Aqsa Martyrs Brigade of attacking Israelis, it is important for Palestinians to see that such attacks may jeopardize the elections now and later — as well as the Israeli withdrawal from Gaza this summer. Prime Minister Tony Blair's message in Jerusalem that terror will undermine any possibility of peace was important, but it must also be reinforced by a declaration that attacks against Israelis will preclude the very calm that Europeans require for sending monitors in to observe the elections.

Third, the United States must work to create an international development fund for the Palestinians. The new Palestinian Authority needs to deliver for the Palestinian people. The Palestinian Authority must be able to provide a social safety net and not leave the provision of after-school programs, clinics and food distribution centers only to Hamas. It must show that life can get better and that its way of fulfilling responsibilities and co-existing with Israel provides the pathway to achieving Palestinian aspirations.

Already, Fatah, Mahmoud Abbas' faction, has dramatically increased its advantage over Hamas in Palestinian opinion polls following Arafat's death. What this reveals is that Palestinians see promise with a new leadership. But the new leadership must show it can deliver on that promise. It is time to get the Arab oil states to help. Saudi Arabia, Kuwait, and the United Arab Emirates have had a $60 billion windfall from the increase in oil prices in the last 10 months. Surely, the United States can call on them publicly to provide 1 percent of that windfall — $600 million — to help the Palestinians create a new reality.

There is an opportunity. However, it is not to tackle the core issues of Jerusalem, borders and refugees right now. No new Palestinian leadership will be able to make any concessions on these issues before it builds its authority. The challenge, therefore, is to make sure that a new leadership delivers on improving the day-to-day reality so it earns the trust of the Palestinian public and becomes able in time to tackle the existential issues of permanent status.

With a Palestinian leadership that fights corruption, builds institutions and a rule of law, and fulfills its responsibilities, especially on security, everything will become possible — including President Bush's vision of a viable Palestinian state co-existing with the Jewish state of Israel. Without it, nothing will change. From that standpoint, the moment is historic, but unlikely to last. Whether the United States will be able to fulfill the Bush vision will depend on seizing the moment; losing it will mean losing it for a long time to come.